FrangipaniBlue there is a proven link, so whether or not you agree with it, the link is there.
OP, I have dozens of meals that take 30 minutes or less to cook. Many of them very ordinary. Sausages and mash; pasta and sauce; stir fry; grilled fish and new potatoes; etc etc
Then add on those that can be done in advance and reheated
Then add on casseroles etc done in a slow cooker or in the oven on a timer
Then add on the meal you made last week, but made double and froze half
That gives you loads of meals which can be on the table for 6:45 or 7:00pm.
I would really really encourage a family dinner together. I have 3 teens and it is a non negotiable, and it is sometimes the only part of the day when we get a whole conversation out of our oldest. Over the last few weeks it has also been a great time for laughing together.
Family mealtimes worth it.
He will be fine eating half an hour later. If he is starving as he walks in the door, let him drink a glass of milk, takes the edge off the feeling of hunger but doesn't effect his appetite. Of a few carrot sticks to munch on while he is waiting.
As a side note, if he has TV on at breakfast lunch and dinner, that is a LOT of TV.
We have a rule (for school times) no TV before school, and then it doesn't go on until 5pm. That way they didn't have too much. Obviously in lockdown it is different, but still, we turn it off.